


Deep Blues

by Mona (RJ92)



Category: Undertale
Genre: 18+ ONLY, Accidental Breath Control, Deepthroating, F/M, Knotting, M/M, No Beta, No Dialogue, Oral Knotting, Oral Sex, Other, blowjob, explicit - Freeform
Language: English
Status: Completed
Published: 2020-10-07
Updated: 2020-10-07
Packaged: 2021-03-08 04:06:35
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 620
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26879413
Author URL: https://archiveofourown.org/users/RJ92/pseuds/Mona
Summary: ((Mature audiences only. Explicit content.))A friend said in passing 'There's a serious lack of oral knotting fics on Ao3' and I took it as a personal challenge. This is a short smutty drabble wherein you give Blue a blowjob with a nice surprise.
Relationships: Sans (Underswap)/Reader
Comments: 3
Kudos: 98





	Deep Blues

**Author's Note:**

  * For [Tia_Bites](https://archiveofourown.org/users/Tia_Bites/gifts).



> No beta, we die like men. Here's another one-shot that doesn't fit into any specific story and instead is presented as its own thing. Hope you enjoy another addition to my sin bin.
> 
> No dialogue, just writing. For Tia_bites, y'all go check out their multiverse Undertale fic, Kick Em To the Curve.

The fingers running soothingly through your hair helped distract from the ache caused by the cock in your throat. It was a welcome distraction, easing the discomfort of having to go beyond your limits to accommodate the girth. It wasn't the first time you'd given Blue a blowjob but it was definitely the first time you'd taken him this deep.

His words of praise made your heart flutter in your chest. His voice was quivering just a little, breaking the confident exterior he always displayed. Knowing that you were the cause of his momentary lapse was thrilling. His compliments and purrs cut off to a hiss when you press forward and nuzzle your nose against the firm manifestation of bright blue magic filling his ribcage and abdominal cavity.

The burn in your lungs was barely worth mentioning. You were going to pass out at this rate but you couldn't bring yourself to care. There were more pressing matters to tend to, like the growing swell of magic at the base of his cock pressing against your lips. You wanted to tell him how much you loved this, loved making him feel so, so good, but you'd always been told never to talk with your mouth full.

Manners matter.

Blue's fingers slide down your scalp and curve around your cheek. You instinctively close your eyes and moan around him. He sucks in a gasp and pushes forward, sending his length farther down your throat. You gag but it doesn't deter either of you. Your hands come up to settle on his thighs and you brace yourself that way, ignoring how the carpet leaves fresh rugburns on your knees and how there are little black spots swimming around the edges of your vision.

Almost there, you think you hear him pant. You take a shallow breath through your nose and hold it. His hand is still on your cheek as he shallowly thrusts with abandon into your mouth. Your teeth graze the top of his cock but he doesn't mind. Every time his growing knot presses against your lips you try to open your mouth a little wider. It's greedy of you, but you want it all.

When you feel his other hand tangle in your hair and pull you in, your eyes flutter shut and your body feels like it's melting. Zaps of pleasure rush through you as he cums, filling your mouth and throat within just a few spurts. You gulp and swallow as well as you can, eager to please and desperate to keep even a single drop of his magic from spilling down your chin.

A sharp, burning sting in your jaw leaves you gasping for breath you can't take, as his knot pushes past your lips and stretches your lips taut. Your eyes squeeze tight and you swallow hard, which draws a cry of startled pleasure from the monster above you. Your cheeks are distended to make room for the knot inside and you know that you look like something right out of a porno.

Blue cums and keeps cumming, hips shuddering and cock throbbing. You can't breathe, but that's okay. You can take it, just a little longer. Just a little more. You barely realize that you're on the brink of actually fainting until you feel another sharp sting and suddenly your throat is free and you're gasping for air with Blue's hands carefully wiping away a mix of drool and cum from your chin, even as it drips down onto your chest and thighs below.

There's a ringing in your ears, too, drowning out anything he's saying. You blink away dark spots and smile adoringly up at him. He always did take your breath away.


End file.
